Brace



F. M. BROWN.

BRACE. APPLICATION FILED MAY 9, 1921.

Patented Oct. 311, 1922 A TTOR/VEYS till Patented 31, 19.132.

BRACE.

Application filed May 9,

To all ii /tom it may concern Be it known that 1, Francis W. BnowN, a citizen of the United States. and a resident of the city of" lVilson, in. the county 01 Carter and State of Oklahoma, have invented a new and useful lmynrovement in Braces, oi? which the following is a full, clear, and exact description.

i Ty invention relates to improvements in braces, and it consists in the conibiinrtions, constructions and arrangements herein described and claimed. 7 1

i-in object of my invention is to provide a brace having a chuck oi greater capacity in a given size than is usual.

A. further object of my invention is to provide in a device ot the character described a chuck having adjustable gripping members adapted to effectively hold tools of various sizes. v p i A further object at my invention is to provide in a device of the character described a chuck having gripping members easy of adjustment.

all further objectof my invention is to provide a device oi the character" described that is relatively simple in construction, and operation, not likely to get out oi? order easily, and thoroughly practical commercially.

Other objects andadvantages will appear in the following specification and the novel features of the invention will be particrb larly pointed out in the appended claim.

My invention is illustrated in the accompanying drawings, forming part of this application, in which- Figure portions thereof being broken away and other portions being shown in section, 1

Figure 2 is a section along the line 2-2 of Fig. 1,

Figure 3 is a section along the line 3-3 of Fig. 2,

Figure 4 is a bottom plan view of a portion of the device, and

Figure 5 is an enlarged perspective of an element embodied in the device.

In carrying out my invention, 1 provide a chuck having a stock or body portion 1 and an integral laterally extending shank or handle portion 2. The shank or handle portion 2 is bent upwardly adjacent to its end and formed with a threaded axial bore or socket 3 adapted to receive the threaded end of a cooperating handle portion i. A pin 5 1 is a side elevation of the device,

1921. Serial No. 468,019.

is provided to prevent disengagement of the tl'ireaded extremity of the handle portion etandthe socket t. i The stock or body portion 1 is substantially cylinrflrical in "form. the outer wall thereof being reduced and threaded at (3 for engagement with an interiorl '"threaded thinible '7. The stock or body portion 1 is formed to provide a substantia ly rectangular axial chamber orrecess 8 of relatively greatlength. The recess 8 extends ironi the lower end of the stock upwardly and the end walls 9 and 10 converge from points in termediate their height to a central opening 11 through the upper wall oi? the titer-k, which is otherwise imperforate. The side walls of the recess 8 are straight and parallel with one another adjacent to their ext emh ties and are formed with similar reces. and 13. respectively, interniediately. as clearly shown in the drawings. The recesses 12 and 13 are defined by inclined walls convergingfrom the lower end of the stock 1 to the ogeningll and the walls of each recess join one another at a right angle.

The chamber or recess 8 provides a guideway for a pair of precisely identical gripping members or dogs IMF-1 1 each of which has its rear face beveled at 15 and 16, and is formed with oppositely extending integral lateral lugs 17 and 18, respectively, intermediate its length. Each gripping member or dog has its front face provided with transversely extending teeth 19 for its entire length, these teeth being intersected intermediately by a longitudinally extending right angular groove or recess 20 in the face of the dog. The lug 17 is provided with an opening 21 therethrougl and the lug 18 is provided with an elongated opening23 therethroug'h. Pins 22 are dis posed in the alined openings 21 and 23. it will be noted that this construction permits the dogs 14 to move angularly with respect to each other.

From the foregoing description oi the various parts of the device, the operation thereof may be readily understood. The parts described may be made of any suitable materials, such as are commonly used in the manufacture of like devices. When the gripping members or dogs 1 11 l are arranged to face each other in the guideway, it is obvious that the elongated opening 23 of one dog willhe opposite the opening 21 of the other dog. The rods 22 and 22 are projected adjacent to its ends,

through alined openings and the ends of these rods are then upset after springs -25 have been placed thereon between opposite lugs to urge the dogs apart. As the gripping members or dogs M-H aremoved upwardly in the recess 8, the upper beveled portion of the outer or rear face of each dog will slidably contact the converging por tion of the adjacent end wall of the recess 8. The movement of the dogs together is occasioned by operation of the thimbleTwhich has a tapering end portion 26 adapted to slidably contact the lower beveled portion of the outer face of each dog as the thimble is turned on the stock or body portion 1. An inwardly extending annularshoulder 27 at the junction of the tapering portion of the thimble with the cylindrical main portion thereof provides a means for limiting the movement of the lower portions of the dogs apart when the thimble engagesthe stock or body portion 1. Since each of the rods v 22 and 22 may oscillate vertically atone end on account oi fitting the elongated opening 23 loosely, it is obvious that the dogs 1 l-1l will remain parallel with one another when urged apart by the springs 25-25 and permittedto move downwardly and outwardly, as when the thimble is turned in one direction, but that the corresponding ends of the dogs may converge and diverge to grip the tapering shank or head of a tool bit 28 when the dogs are moved inwardly and upwardly against the tension of the springs 25-25 when the thimble is moved in the opposite direction on the body portion 1. It is obvious that tool bits ranging llL'SlZG from a very small size to a relatively large size may be effectively gripped between the serrated faces or jaws of the dogs lllt and that my device has a greater capacity in a given size than is ordinary. Since a larger portion of the tool engaged is gripped in my device than is ordinarily the case, it is apparent that the tool bits will be more securely held in operative position than has heretofore been possible in any device of like character of which I am aware. My improved device can be operated quickly and easily to engage and disengage tools, as desired.

I claim: v In a'device of the type described, a body portion having a tapering square centrally disposed opening therein. said body having diametrically disposed. converging grooves communicating with the opening, a pair of dogs, each dog having two laterally project ing lugs with openings therein, one of the openings of each dog being elongated, pins disposed in the alined openings of each dog, coil'springs carried by said pins and being disposed between said dogs, anda cylindrical casing carried by said body portion and housing said dogs, said casing being adapted, when rotated in one direction, to move said dogs toward each other the elongated openings permitting said dogs to move angularly with respect to each other.

FRANCIS M. BROWN. 

